diff --git a/Controller/ApiController.php b/Controller/ApiController.php
index d65d721..08d093b 100644
--- a/Controller/ApiController.php
+++ b/Controller/ApiController.php
@@ -32,7 +32,7 @@ use Modules\QA\Models\QABadgeMapper;
  * @link       http://website.orange-management.de
  * @since      1.0.0
  */
-class ApiController extends Controller
+final class ApiController extends Controller
 {
     public function apiQAQuestionCreate(RequestAbstract $request, ResponseAbstract $response, $data = null) : void
     {
diff --git a/Controller/BackendController.php b/Controller/BackendController.php
index 8eb845d..9227491 100644
--- a/Controller/BackendController.php
+++ b/Controller/BackendController.php
@@ -32,7 +32,7 @@ use Modules\QA\Models\QABadgeMapper;
  * @link       http://website.orange-management.de
  * @since      1.0.0
  */
-class BackendController extends Controller
+final class BackendController extends Controller
 {
     /**
      * @param RequestAbstract  $request  Request
diff --git a/Models/QAAnswer.php b/Models/QAAnswer.php
index 6b86b7f..4d0b29a 100644
--- a/Models/QAAnswer.php
+++ b/Models/QAAnswer.php
@@ -22,7 +22,7 @@ namespace Modules\QA\Models;
  * @link       http://website.orange-management.de
  * @since      1.0.0
  */
-class QAAnswer implements \JsonSerializable
+final class QAAnswer implements \JsonSerializable
 {
     private $id = 0;
 
diff --git a/Models/QAAnswerMapper.php b/Models/QAAnswerMapper.php
index 0c913e4..7d15768 100644
--- a/Models/QAAnswerMapper.php
+++ b/Models/QAAnswerMapper.php
@@ -28,7 +28,7 @@ use phpOMS\DataStorage\Database\RelationType;
  * @link       http://website.orange-management.de
  * @since      1.0.0
  */
-class QAAnswerMapper extends DataMapperAbstract
+final class QAAnswerMapper extends DataMapperAbstract
 {
 
     /**
diff --git a/Models/QABadge.php b/Models/QABadge.php
index 4b287ca..94dc113 100644
--- a/Models/QABadge.php
+++ b/Models/QABadge.php
@@ -22,7 +22,7 @@ namespace Modules\QA\Models;
  * @link       http://website.orange-management.de
  * @since      1.0.0
  */
-class QABadge implements \JsonSerializable
+final class QABadge implements \JsonSerializable
 {
     private $id = 0;
 
diff --git a/Models/QABadgeMapper.php b/Models/QABadgeMapper.php
index a146244..8e10dde 100644
--- a/Models/QABadgeMapper.php
+++ b/Models/QABadgeMapper.php
@@ -27,7 +27,7 @@ use phpOMS\DataStorage\Database\RelationType;
  * @link       http://website.orange-management.de
  * @since      1.0.0
  */
-class QABadgeMapper extends DataMapperAbstract
+final class QABadgeMapper extends DataMapperAbstract
 {
 
     /**
diff --git a/Models/QACategory.php b/Models/QACategory.php
index 6225f66..1e0cfdc 100644
--- a/Models/QACategory.php
+++ b/Models/QACategory.php
@@ -22,7 +22,7 @@ namespace Modules\QA\Models;
  * @link       http://website.orange-management.de
  * @since      1.0.0
  */
-class QACategory implements \JsonSerializable
+final class QACategory implements \JsonSerializable
 {
     private $id = 0;
 
diff --git a/Models/QACategoryMapper.php b/Models/QACategoryMapper.php
index f42b54f..1a13fc0 100644
--- a/Models/QACategoryMapper.php
+++ b/Models/QACategoryMapper.php
@@ -27,7 +27,7 @@ use phpOMS\DataStorage\Database\RelationType;
  * @link       http://website.orange-management.de
  * @since      1.0.0
  */
-class QACategoryMapper extends DataMapperAbstract
+final class QACategoryMapper extends DataMapperAbstract
 {
 
     /**
diff --git a/Models/QAQuestion.php b/Models/QAQuestion.php
index adfa77e..0fb84cf 100644
--- a/Models/QAQuestion.php
+++ b/Models/QAQuestion.php
@@ -22,7 +22,7 @@ namespace Modules\QA\Models;
  * @link       http://website.orange-management.de
  * @since      1.0.0
  */
-class QAQuestion implements \JsonSerializable
+final class QAQuestion implements \JsonSerializable
 {
     private $id = 0;
 
diff --git a/Models/QAQuestionMapper.php b/Models/QAQuestionMapper.php
index 78aef50..3f8b6dd 100644
--- a/Models/QAQuestionMapper.php
+++ b/Models/QAQuestionMapper.php
@@ -28,7 +28,7 @@ use phpOMS\DataStorage\Database\RelationType;
  * @link       http://website.orange-management.de
  * @since      1.0.0
  */
-class QAQuestionMapper extends DataMapperAbstract
+final class QAQuestionMapper extends DataMapperAbstract
 {
 
     /**